For the past two months the satellite radios we fitted to AW and 09 have revealed a huge amount about the birds’ fishing habits. Now comes an even more exciting time. Migration. Male Ospreys usually wait until the last of their chicks has migrated before they head south, but that’s not what AW has done. By Saturday morning only one of his three youngsters had left the Site O nest site (nest on private land near Rutland Water), and we expected him to linger into the early part of September. We were wrong!

After fishing in the reservoir at 8am, AW started his migration. By 11am he was 50km south of Rutland Water heading purposefully SE at 37kph and an hour later he was passing just to the east of Stevenage at 36kph at an altitude of just 33m. His south-easterly course then took him around the eastern edge of London and into Kent. At 2pm he was over Staplehurst still heading SE and by 3pm he was heading out across the English channel, flying 80m above the waves at 40kph. Birdwatchers at Dungerness may well have seen him heading out to see. He had covered almost 230km in just over five hours of migrating.

AW’s radio is collecting data every hour, but it is still on a three day duty cycle, meaning we won’t receive his latest position until tomorrow. It will be fascinating to see how far south he has travelled. This is his fifth autumn migration and so he will probably be heading to a regular stop-over site, perhaps in France or Spain. As soon as the data comes in, we’ll update you.

Although AW is heading south, his mate has remained at the nest – and she will probably stay there until the remaining two chicks have left.